The Saints have struggled away from home, while the Seahaws have battled issues along their O-line. (Scott Eklund/AP)

No contender is perfect, not even the Seattle Seahawks, arguably the best team in football. In the latest Cover-Two, Chris Burke and Doug Farrar debate the biggest questions surrounding each and every division leader.

Philadelphia Eagles

Chris Burke: Was that stretch of good defense a mirage?

From Week 5 through Week 14, the Eagles posted a 7-1 record while allowing just 18.1 points per game. And then they coughed up 49 to the Adrian Peterson-less Vikings last Sunday. Philadelphia has made marked improvement on defense this season, but there are legitimate questions about that unit moving forward. Not a single opponent in that 7-1 stretch currently sits in playoff position, and the Eagles still rank 31st against the pass. They close with two teams, Chicago and Dallas, averaging more than 28 points per game.

Doug Farrar: Which defense will show up?

Over the last month, the Eagles were able to gain a lot of ground in the NFC East, and that had as much to do with Billy Davis' defense as anything Chip Kelly was doing on the other side of the ball. However, in last Sunday's loss to the Minnesota Vikings, defensive failures were evident at every level. Minnesota used a expansive palette of formations to confuse Philly's front seven in the run game, Davis' linemen were overpowered by extra blockers, and switches in coverage did little to stop Matt Cassel from looking a little too much like Tom Brady. Davis must fix what ails that defense if the Eagles expect to be any more than a one-and-done. That or Nick Foles had better get ready to throw seven touchdowns in every game.

Chicago Bears

Burke:Can they stop the run?

Similar issue in Chicago as in Philadelphia (though the Bears' QB conundrum stands as a far greater headache). The Bears have been gashed on the ground all season, to the tune of a league-worst 152.4 yards per game. Up in Weeks 16 and 17, respectively: LeSean McCoy and Eddie Lacy. Chicago probably has to win both of its remaining matchups to hold on to the NFC North, so the defense at least has to do its part.

The Bears are coming off their best performance against the run in more than two months -- they held Cleveland to 93 yards rushing in Week 15.

Farrar: Where did the pass rush go?

Yes, Chicago's run defense is a clear problem. But the pass rush has disappeared as well. The Bears rank last in the league with 26 sacks, which wouldn't be as much of a problem if their defenders were getting hits and hurries on quarterbacks in place of those sacks. But that's not happening at a high level, either. Julius Peppers has just 10 combined sacks and hits, as does Shea McClellin -- and they're tied for the team lead in that category. That won't feed the bulldog in an NFL playoff picture full of impact quarterbacks.

New Orleans Saints

Burke:Will they solve their road woes?

Most teams in the NFL are worse away from home, and several contenders have struggled there this season. (Chicago, New England and Cincinnati are all under .500 in road games.) But the difference between the Superdome Saints and the visiting Saints has been striking. Not only is New Orleans a mere 3-4 on the road, but also it's averaging fewer than 19 points per game; it scores 32.8 per home game.

Week 16 takes the Saints to Carolina, with the division title on the line. A loss likely would mean needing three road wins to get to the Super Bowl.

Farrar: Will Sean Payton's impulse moves make any difference?

New Orleans' head coach demoted left tackle Charles Brown after Brown gave up two sacks in the Saints' loss to the St. Louis Rams last Sunday. Rookie Terron Armstead, a fourth-round pick with no regular-season experience, will start in the short term, and we'll see how that plan works against the pass rushers sent by the Carolina Panthers and Tampa Bay Buccaneers in Weeks 16 and 17 -- not to mention what may await them in the playoffs. Payton also cut struggling kicker Garrett Hartley and signed Shayne Graham in his place, through that move was probably justified.

"Sean flat-out said, 'There's probably going to be some changes made around here, and some of you won't like it,'" quarterback Drew Brees said after that loss.

Yes, such moves put players on notice. But is that the best thing so close to the playoffs, when cohesion is generally a primary issue? We shall see.

Seattle Seahawks

Burke: Which team poses the biggest threat?

Internally, the Seahawks' most pressing concerns are in the secondary, where Brandon Browner was just suspended indefinitely; and on the offensive line, which has permitted 36 sacks of Russell Wilson. The former may cause more sleepless nights, especially since Seattle was bounced from the playoffs last year after giving up a couple of late passing plays to Atlanta's Matt Ryan.

Barring a collapse over the final two weeks, though, Seattle can sit back and wait for its playoff foes to visit the Pacific Northwest. So there's a little time to scour the landscape. And the Seahawks slammed both the 49ers and Saints in Seattle already this season (though San Francisco won the backend of that divisional home-and-home). Would either strike fear into the Seahawks' hearts? How about the NFC North or NFC East champ -- any of the possibilities there carry explosive offenses.

Seattle's going to enter the playoffs as a Super Bowl favorite and as, from what we've seen so far, the least-flawed team in football.

Farrar: Will the guards hold up?

It's tough to look at the 12-2 Seahawks and find an obvious flaw, but when one looks at the offensive line, Seattle's guards paint a less-than-rosy picture. Veteran Paul McQuistan has allowed no sacks and just one quarterback hurry in the four games since he moved back to guard from tackle in place of the injured Russell Okung, but he hasn't been strong enough opening holes in the run game. James Carpenter has managed to avoid the injury bug this season, but his performances have not been stellar, either. Marshawn Lynch's dynamic running style hides a multitude of blocking sins, and the Seahawks can use Lynch more in the passing game as they did against the Giants last Sunday, but this team has a clear offensive philosophy that centers around the run game and the play-action pass. And without quality interior protection, both primary aspects can be affected by better defenses. Seattle faces two such defenses in its last two regular-season games -- the Arizona Cardinals and St. Louis Rams, who can mess quarterbacks up and force running backs to consider alternate careers on their best days.

New England Patriots

Burke:Can the running backs carry them?

With Rob Gronkowski out of the lineup, there are going to be more opportunities for the guys out of New England's backfield. And whether that means LeGarrette Blount up the middle or Shane Vereen split out in the slot, the Patriots' running backs could be the key positional group come the postseason.

New England's run game has been undervalued for some time -- it's 12th in the league right now, despite starting tackle Sebastian Vollmer and now Gronkowski landing on injured reserve. With Blount, Vereen, Stevan Ridley and Brandon Bolden, this team has a variety of options for a number of different sets. But can they trust any of them to take charge if need be?

Farrar: How will they create explosive plays in the passing game?

Obviously, the big news about New England's offense is that without Rob Gronkowski, Tom Brady has struggled to make the kinds of explosive plays in the passing game that every team needs at some point in the modern NFL postseason. And it's not just his receivers -- Brady is also playing behind an injury-affected offensive line (Logan Mankins may have to shift outside to left tackle with Nate Solder's head injury). Brady has been far, far more efficient with Gronkowski in the lineup than without, and even his second-level targets are struggling with injuries. Factor in that the Patriots defense is not the kind of unit that will make up for such offensive deficiencies, and you have a team that could go anywhere from the AFC's second seed to the outside looking in over the next two games.

Cincinnati Bengals

Burke: Will Andy Dalton ever earn our trust?

Inevitably, when talking about the Bengals' chances in any given season, the discussion circles back to Dalton. His 2013 numbers almost identically match those from 2012 (27 touchdowns and 16 interceptions both seasons, a 61.5 completion percentage in '13 compared to 62.3 last year). And '12 ended with Dalton laying an egg in a playoff loss to Houston. There have been stretches -- like a four-game win streak over the Patriots, Bills, Lions and Jets -- where Dalton has found a groove. Cincinnati needs him to do so again in Weeks 16 and 17 and on into the playoffs.

Farrar:Can the defense put things back together without Geno Atkins?

It's often said that great athletes leave their biggest impression in their absence, and that's certainly true with Atkins, the Pro Bowl defensive tackle who was lost for the season to a torn ACL in early November. Since his injury, the Bengals' quarterback pressures have decreased and their missed tackles have increased. Atkins dealt with double teams on nearly every play, and now, those freed-up offensive linemen are hitting other targets. Cincinnati's defense has covered up Andy Dalton's flaws at times in the past, but a deep playoff run will be on the offense now more than ever.

Indianapolis Colts

Burke: Is the offensive line good enough?

That Andrew Luck has been sacked only 30 times this season is more a tribute to his ability to feel pressure and escape the pocket than it is any indication of great Indianapolis blocking. The line has been shaky at best, with the Colts often fighting to establish a run-pass balance and Luck running for his life when they take to the air.

As things stand right now, the Colts would have to open the postseason against Kansas City's ferocious pass rush. Such a matchup would be frightening on paper.

Farrar: Can this playoff team start looking like a playoff team?

The Colts have default playoff positioning due to their status as AFC South champions, but backing into a title atop a really bad division is one thing -- taking on the best teams in the postseason is entirely another. And right now, Indianapolis doesn't look like that type of team. The Colts established a positive point differential with last Sunday's 25-3 thrashing of the Texans, but they've been alternating wins and losses since their three-game win streak ended on Oct. 6. The offense sputters most weeks, the running game is a consistent issue and if this team has to play catch-up on the road -- which it would probably have to at some point in the playoffs -- it's not clear that it is equipped to do so. At least Andrew Luck is a bastion of stability no matter where he goes -- he has a passer rating of 85.2 at home, and 85.3 on the road.

Denver Broncos

Burke: Will Wes Welker return?

The Broncos signed Welker this past offseason because they felt he was a missing piece on offense, and never have they been proven more correct than when he was out of the lineup last week. Without their reliable slot receiver, Denver's offense sputtered against San Diego, particularly on third downs (2-of-9).

Peyton Manning's offense may be without Welker (concussion) in Weeks 16 and 17. A loss either week could drop Denver out of the AFC (and AFC West) lead.

Farrar: Will a patchwork defensive line hold up through the postseason?

Denver doesn't have a specific timeline on the return of Derek Wolfe, and Kevin Vickerson is out for the rest of the season with a hip injury. The Broncos signed end Jeremy Mincey to fill in, as Mincey had done well for Jack Del Rio when Denver's current defensive coordinator was the Jacksonville Jaguars' head coach. Denver will need Mincey to show that he still has something left in the tank. Denver is ranked 19th against the pass in Football Outsiders' metrics, and outside of Shaun Phillips and Von Miller, there isn't much consistent pass rush on the roster. That impacts a Denver secondary affected all season by Champ Bailey's health issues. The underrated Malik Jackson must continue to be a factor up front.